| 摘要 |
The invention relates to a multifunctional acrylated product with a mean functionality f greater than 3 and a density of acrylates ranging from 4 to 12 mmol per g, which is the product of reaction by esterification and by etherification, via a Michael addition reaction, between at least one polyol R(OH)m with a functionality m of at least 3 and acrylic acid (R1OH), with the carboxyl groups of acrylic acid being in deficit relative to the hydroxyl groups of said polyol, and which final product comprises at least 3 acrylates defined according to general formula (I) below and corresponding to n = 0, n = 1, n = 2: (R1O)-[-R[OR1]m-2-O-(C=O)-CH2-CH2-O-]n-R-(OR1)m-1 (I) with R1 being the acryloyl radical (-(C=O)-CH=CH2), R being the residual radical of said polyol R(OH)m and n being the number of ether-ester repeating units obtained by Michael addition of the residual OH groups of the hydroxylated acrylate esters formed by partial esterification of said polyol (Michael addition) to the acrylate groups of said acrylate esters. The invention also relates to a process for preparing said product, to crosslinkable compositions comprising same and to the use thereof in coatings, sealing compositions, moulding compositions, composite compositions or chemical sealing compositions. A particular advantage of these compositions is the low shrinkage thereof despite the high functionality thereof. |
